Hermaphroditic multi-contact reed switch

ABSTRACT

A HERMAPHRODITIC MULTI-CONTACT REED SWITCH INCLUDES A TUBULAR ENVELOPE HAVING A PAIR OF SUBSTANTIALLY IDENTICAL HEADERS SEALED INTO THE OPPOSITE ENDS AND CONTAINS AN INERT ATMOSPHERE. EACH OF THE HEADERS INCLUDES A PLURALITY OF SWITCH MEMBERS HAVING A MAGNETIZABLE PORTION EXTENDING INTERIORLY OF THE ENVELOPE AND IN LONGITUDINALLY OVERLAPPING RELATIONSHIP WITH THE MAGNETIZABLE PORTION OF THE SWITCH MEMBERS OF THE OPPOSITE HEADER. THE LONGITUDINAL   OVERLAPPING MAGNETIZABLE PORTIONS OF THE MATCHING SWITCH MEMBERS OF THE OPPOSING HEADERS HAVE A DESIRED GAP THEREBETWEEN WHICH IS DEPENDENT UPON THE CIRCUMFERENTIAL DISPLACEMENT OF ONE HEADER WITH RESPECT TO THE OTHER.

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HERMAPHRODITIC MUL'I'I-CONTAC'I' REED SWITCH Original filed Marah 14,1968 2 Sheets-She et 1 INVENTOR. RALPH E. NEUBER v w iD- ATTOR NET March9, 1971 i R. E. NEUBER 3,563,310

Q I HERMAPHRODITIC MULTI-CONTACT REED SWITCH Original Filed March 14,1968 2 Sheets-Sheet 2 FORM A PAIR OF SIMILAR HEADERS INCLUDING ANINSULATOR AND SWITCH MEMBERS CIRCUMFERENTIALLY'ROTATE ONE HEADER wnuRESPECT TO THE OTHER HERMET ICALLY SEAL HEADERS IN OPPOSITE ENDS OFTUBULAR ENVELOPE INVENTOR. RALPH E. NEUBER m CIJ ATTORNEY United StatesPatent 3,568,310 HERMAPHRODITIC MULTI-CONTACT REED SWITCH Ralph E.Neuber, Seneca Falls, N.Y., assignor to Sylvania Electric Products Inc.

Original application Mar. 14, 1968, Ser. No. 713,216, now Patent No.3,471,813, dated Oct. 7, 1969. Divided and this application Apr. 17,1969, Ser. No. 816,990

Int. Cl. H01h 11/00 US. Cl. 29-622 2 Claims ABSTRACT OF THE DISCLOSURE Ahermaphroditic multi-contact reed switch includes a tubular envelopehaving a pair of substantially identical headers sealed into theopposite ends and contains an inert atmosphere. Each of the headersincludes a plurality of switch members having a magnetizable portionextending interiorly of the envelope and in longitudinally overlappingrelationship with the magnetizable portion of the switch members of theopposite header. The longitudinal overlapping magnetizable portions ofthe matching switch members of the opposing headers have a desired gaptherebetween which is dependent upon the circumferential displacement ofone header with respect tothe other.

CROSS-REFERENCE TO RELATED APPLICATION This application is a division ofS.N. 713,216, filed Mar. 14, 1968, now US Pat. 3,471,813 which issuedOct. 7, 1969, and assigned to the assignee of the present invention.

BACKGROUND OF THE INVENTION The prior art suggests numerous so-calledreed switches wherein a pair of magnetizable contact members aredisposed in overlapping spaced relationship with in an envelope andactivated by application of controllable magnetic field. Also, the priorart suggests numerous similar devices wherein a number of suchcontacting members are included within the same envelope.

Although many of the above-mentioneddevices have provided excellentservice in numerous applications, it has been found that there arecertain applications wherein the known structure leaves something to bedesired. More specifically, it has been found that known reed switchstructures usually include switch members sealed into the ends of theenvelope which tends to provide a non-uniform seal and a non-uniformspacing intermediate the mag- 0 netizable switch members. Also, suchsealing techniques wherein glass-to-metal seals, for example, areemployed require delicate controls to prevent oxidation of the metalswitch members. Moreover, all of the switch members of the knownmultiple-contact devices are not concentric with respect to the envelopeand to the energizing means surrounding the envelope which tends tocause a nonuniform magnetic field intensity insofar as a multiplecontactdevice is concerned.

OBJECTS AND SUMMARY OF THE INVENTION for the contacts of ahermaphroditic multi-contact reed switch. These and other objects andadvantages are achieved 1n one aspect of the invention by ahermaphroditic multicontact reed switch having a pair of substantiallyidentical headers each including an insulator support and a plurality ofswitch members embedded therein and extending therethrough. The headersare circumferentially displaced with respect to one another and sealedinto opposite ends of a tubular envelope to provide a spacedlongitudinal overlapping of the switch members which are activated by amagnetic field developing means surrounding the envelope.

The hermaphroditic multi-contact reed switch is constructed by a processwhich includes fabricating a pair of substantially identical headers,circumferentially rotating the headers with respect to one another, andhermetically sealing the headers into opposite ends of a tubularenvelope.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a preferredembodiment of a hermaphroditic multi-contact reed switch;

FIG. 2 is a plan view of the embodiment of FIG. 1, and

FIGS. 3, 4 and 5 are embodiments of headers suitable for the embodimentof FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding ofthe present invention, together with other and further objects,advantages and capabilities thereof, reference is made to the followingdisclosure and accompanying drawings.

Referring to the drawings, FIG. 1 illustrates a hermaphroditicfour-contact reed switch. The switch includes a tubular envelope 7 of amaterial such as glass and has a pair of opposite ends 9 and 11. A pairof substantially similar headers, 13 and 15 are hermetically sealed intothe opposite ends 9 and 11 of the envelope 7.

The headers 13 and 15 each include an insulator support 17 such asglass, wherein a plurality of switch members 19 are embedded. The switchmembers 19 each include a magnetizable portion 21 which is flexible andof a material such as iron or a nickel-iron alloy and extends interiorlyof the envelope 7. Also, each of the switch members 19 includes aconnector portion 23 extending exteriorly of the envelope 7 to providean electrical connecting means.

Further, the longitudinal axis of each of the magnetizable portions 21is displaced from the longitudinal axis of the connector portions 23 ina direction substantially normal to these longitudinal axes. Also, thedisplacement of each of the magnetizable portions 21 from thelongitudinal axis of the connector portion 23 is substantially one-halfthe total desired gap 25 or distance intermediate a pair of magnetizableportions 21.

In this particular embodiment, the four switch members 19 are spaced inquadrature as illustrated in the plan view of FIG. 2. These quadraturespaced switch members 19 form two diametrically opposing pairs with themagnetizable portions 21 of one pair formed such that the diametricdistance X between the longitudinal axes thereof is greater than thediametric distance Y between the longitudinal axes of the connectorportions 23. The other pair is formed in an opposite fashion in that thediametric distance A between the longitudinal axes of the magnetizableportions 21 is less than the diametric distance 8 between thelongitudinal axes of the connnector portions 23.

As mentioned above, the headers 13 and 15 are hermetically sealed toopposite ends 9 and 11 of the envelope 7, and provide a longitudinaloverlapping of the magnetizable portion 21 of the switch members 19extending interiorly of the envelope 7 from each of the headers 13 and15. Also, the headers 13 and 15 are in circumferentially displacedrelationship with respect to one another to provide a desired gap 25 ordistance intermediate each pair of longitudinally overlappingmagnetizable portions 21. In this particular instance, thecircumferential relationship is a quadrature relationship although it isobvious that other switch member forms and circumferential relationshipsare applicable and appropriate.

The pairs of magnetizable portions 21 forming each one of the gaps 25are equi-distantly spaced from the circumference of the tubular envelope7 and a magnetic field developing means 27 such as an electromagnet forinstance, surrounds the tubular envelope 7. Thus, each pair ofmagnetizable portions 21 of the switch members 19 is equi-distantlyspaced from the magnetic field developing means 27 and subjected tosubstantially the same magnetic field intensity.

Referring back to the headers 13 and 15, FIGS. 3, 4, and illustrateseveral suitable embodiments. In FIG. 3 a plurality of switch members 29are embedded in and pass through an insulator 31 such as glass. Each ofthe switch members 29 has a magnetizable portion 33 and a connectorportion 35 which extend outwardly in Opposite directions from theinsulator 31. Also, the magnetizable portion 33, which is both magneticand flexible, is formed such that the insulator 31 serves as a rigid anduniform base whereon the cantilevered magnetizable portion 33 bends.

FIG. 4 is a structure somewhat similar to FIG. 2. Herein, each of theswitch members 29 has beads 37 of the same material as the insulator 31bonded to the insulator 31 and surrounding, supporting and sealed toboth the magnetizable and connector portions 33 and 35 respectively.Also, a tubular exhaust stem 39 is affixed to the insulator 31 in amanner well known in the art to provide a means for replacing theatmosphere of the device with desired inert atmosphere.

Also, FIG. 5 illustrates a plurality of switch members 29 sealed intoand passing through an insulator 31 and a button 41 bonded thereto. Inthis instance, the button 41 not only enhances the rigidity and sealingof the switch members 29 but also serves to protect the sealintermediate the switch members 29 and insulator 31 from thermal shockupon application of heat, soldering for instance, to the switch members29.

As to the construction of a hermaphroditic multi-contact reed switch,reference is made to the flow chart of FIG. 6. Therein, a plurality ofsimilar headers are fabricated by sealing a plurality of switch membersincluding magnetizable and connector portions into an insulator.Obviously, the switch members are preferably of the preformed varietybut may be formed after embedment in the insulator. Also, the formedswitch members are readily adapted to both spacing adjustment andcleaning after having been sealed into the insulator.

Then a pair of the headers are circumferentially rotated with respect toone another to provide a desired gap intermediate associated pairs ofmagnetizable portions. This pair of headers is hermetically sealed toopposite ends of a tubular envelope which, in the preferred embodiment,involves a glass-to-glass sealing technique and a relatively smalldistortion of the envelope to provide contact thereof with the headers.Moreover, the atmosphere Within the envelope may then be replaced by adry inert atmosphere utilizing an exhaust tube in a manner well-known inthe art.

Thus, there has been provided a unique hermaphroditic 4 multi-contactreed switch having numerous advantages over other known reed switches.The multi-contact switch is volumetrically efficient as compared withsingle-contact devices providing a consequent reduction in cost percontact. Also, the header-type construction lends itself to theformation of a rigid and uniform support whereon the flexiblemagnetizable portion of the switch members is dependent. Further, theheader-type construction provides individual sealing of the switchmembers to the headers and hermetic sealing of the headers to theenvelope which not only permits cleaning and adjustment of the switchmembersbut also a relatively small distortion of the envelope whereinthe headers are hermetically sealed. Additionally, the header-typeconstruction facilitates circumferential displacement of the headerswith respect to one another prior to scaling and enhances compensationfor distortion of the switch members due to handling and transfer duringfabrication.

Moreover, the hermaphroditic form of the headertype construction iseconomical of apparatus, time, and inventory of parts.

While there has been shown and described what is at present consideredthe preferred embodiments of the in vention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention as defined by the appendedclaims.

I claim: 1. A hermaphroditic multi-contact reed switch fabricatingprocess comprising the steps of:

forming a pair of substantially similar headers, each header having aninsulator with four switch members identically arranged thereabout andembedded therein and extending therethrough, said switch members beingspaced in quadrature relationship forming two diametrically opposingpairs, one of said pairs having a larger diametrical spacing than theother;

aligning and overlapping opposing pairs of switch members havingdifferent diametrical spacings by juxtaposing the headers with respectto each other; and

hermetically sealing said pair of headers in opposite ends of a tubularenvelope to provide a longitudinal overlapping of the switch members ofsaid pair of headers, whereby said overlapping switch members have gapstherebetween and said gaps are disposed a uniform radial distance fromsaid envelope circumference.

2. The fabricating process of claim 1 including the step of replacingthe atmosphere or said envelope with a dry and inert atmosphere.

References Cited UNITED STATES PATENTS 2,407,742 9/ 1946 Harries29-25.16 2,411,548 11/1946 Laico 29-25. 16X 2,204,217 6/1940 Herriger2925.16X 2,225,465 12/ 1940 Scharfnagel 29-25.16 3,134,868 5/1964 Shine.

3,248,498 5/ 1966 Thompson.

JOHN F. CAMPBELL, Primary Examiner R. W. CHURCH, Assistant Examiner US.01. X.R.

